Engine block heater extension



FIG. 1 is a perspective view of an engine block heater extension showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right view thereof;

FIG. 5 is a left view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

FIG. 1 is on an enlarged scale. 

The ornamental design for an engine block heater extension, as shown. 